[Gradle] fix esql compile cacheability (#111651)

- We use a JvmCommandlineprovider to reference the generated source folder and keep gradle cache happy

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/util/SourceDirectoryCommandLineArgumentProvider.java

@@ -0,0 +1,36 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+package org.elasticsearch.gradle.internal.util;
+
+import org.gradle.api.file.Directory;
+import org.gradle.api.tasks.InputDirectory;
+import org.gradle.api.tasks.PathSensitive;
+import org.gradle.api.tasks.PathSensitivity;
+import org.gradle.process.CommandLineArgumentProvider;
+
+import java.util.Arrays;
+
+public class SourceDirectoryCommandLineArgumentProvider implements CommandLineArgumentProvider {
+
+    private final Directory sourceDirectory;
+
+    public SourceDirectoryCommandLineArgumentProvider(Directory sourceDirectory) {
+        this.sourceDirectory = sourceDirectory;
+    }
+
+    public Iterable<String> asArguments() {
+        return Arrays.asList("-s", sourceDirectory.getAsFile().getAbsolutePath());
+    }
+
+    @InputDirectory
+    @PathSensitive(PathSensitivity.RELATIVE)
+    public Directory getSourceDirectory() {
+        return sourceDirectory;
+    }
+}

x-pack/plugin/esql/build.gradle

@@ -1,5 +1,6 @@
 import org.elasticsearch.gradle.internal.info.BuildParams
 import org.elasticsearch.gradle.internal.precommit.CheckForbiddenApisTask;
+import org.elasticsearch.gradle.internal.util.SourceDirectoryCommandLineArgumentProvider;
 
 apply plugin: 'elasticsearch.internal-es-plugin'
 apply plugin: 'elasticsearch.internal-cluster-test'
@@ -50,7 +51,7 @@ dependencies {
 }
 
 tasks.named("compileJava").configure {
-  options.compilerArgs.addAll(["-s", "$projectDir/src/main/generated"])
+  options.compilerArgumentProviders.add(new SourceDirectoryCommandLineArgumentProvider(project.layout.projectDirectory.dir("src/main/generated")))
   // IntelliJ sticks generated files here and we can't stop it....
   exclude { it.file.toString().contains("$projectDir/src/main/generated-src/generated") }
 }